Hello,
This can be due to frenulum breve or phimosis. It is a condition in which the frenulum of the penis is short and restricts the movement of the prepuce, which may interfere with normal sexual activity. It is treated by frenuloplasty, frenectomy, or circumcision.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
This is known as 'Phimosis'.Do meet your doctor. Nowadays external applications are available to release the tightness.